外文翻译--注塑模的单浇口优化.doc

1外文翻译毕业设计题目：SD2106鼻毛修剪器上下盖造型及模具设计原文1：Singlegateoptimizationforplasticinjectionmold*译文1：注塑模的单浇口优化2Singlegateoptimizationforplasticinjectionmold*Abstract:Thispaperdealswithamethodologyforsinglegatelocationoptimizationforplasticinjectionmold.Theobjectiveofthegateoptimizationistominimizethewarpageofinjectionmoldedparts,becausewarpageisacrucialqualityissueformostinjectionmoldedpartswhileitisinfluencedgreatlybythegatelocation.Featurewarpageisdefinedastheratioofmaximumdisplacementonthefeaturesurfacetotheprojectedlengthofthefeaturesurfacetodescribepartwarpage.Theoptimizationiscombinedwiththenumericalsimulationtechnologytofindtheoptimalgatelocation,inwhichthesimulatedannealingalgorithmisusedtosearchfortheoptimum.Finally,anexampleisdiscussedinthepaperanditcanbeconcludedthattheproposedmethodiseffective.INTRODUCTIONPlasticinjectionmoldingisawidelyused,complexbuthighlyefficienttechniqueforproducingalargevarietyofplasticproducts,particularlythosewithhighproductionrequirement,tighttolerance,andcomplexshapes.Thequalityofinjectionmoldedpartsisafunctionofplasticmaterial,partgeometry,moldstructureandprocessconditions.Themostimportantpartofaninjectionmoldbasicallyisthefollowingthreesetsofcomponents:cavities,gatesandrunners,andcoolingsystem.LamandSeow(2000)andJinandLam(2002)achievedcavitybalancingbyvaryingthewallthicknessofthepart.Abalancefillingprocesswithinthecavitygivesanevenlydistributedpressureandtemperaturewhichcandrasticallyreducethewarpageofthepart.Butthecavitybalancingisonlyoneoftheimportantinfluencingfactorsofpartqualities.Especially,theparthasitsfunctionalrequirements,anditsthicknessesshouldnotbevariedusually.Fromthepointviewoftheinjectionmolddesign,agateischaracterizedbyitssizeandlocation,andtherunnersystembythesizeandlayout.Thegatesizeandrunnerlayoutareusuallydeterminedasconstants.Relatively,gatelocationsandrunnersizesaremoreflexible,whichcanbevariedtoinfluencethequalityofthepart.Asaresult,theyareoftenthedesignparametersforoptimization.LeeandKim(1996a)optimizedthesizesofrunnersandgatestobalancerunnersystemformultipleinjectioncavities.Therunnerbalancingwasdescribedasthe3differencesofentrancepressuresforamulti-cavitymoldwithidenticalcavities,andasdifferencesofpressuresattheendofthemeltflowpathineachcavityforafamilymoldwithdifferentcavityvolumesandgeometries.Themethodologyhasshownuniformpressuredistributionsamongthecavitiesduringtheentiremoldingcycleofmultiplecavitiesmold.Zhaietal.(2005a)presentedthetwogatelocationoptimizationofonemoldingcavitybyanefficientsearchmethodbasedonpressuregradient(PGSS),andsubsequentlypositionedweldlinestothedesiredlocationsbyvaryingrunnersizesformulti-gateparts(Zhaietal.,2006).Aslarge-volumepart,multiplegatesareneededtoshortenthemaxiinjectionpressure.Themethodispromisingfordesignofgatesandrunnersforasinglecavitywithmultiplegates.Manyofinjectionmoldedpartsareproducedwithonegate,whetherinsinglecavitymoldorinmultiplecavitiesmold.Therefore,thegatelocationofasinglegateisthemostcommondesignparameterforoptimization.AshapeanalysisapproachwaspresentedbyCourbebaisseandGarcia(2002),bywhichthebestgatelocationofinjectionmoldingwasestimated.Subsequently,theydevelopedthismethodologyfurtherandappliedittosinglegatelocationoptimizationofanLshapeexample(Courbebaisse,2005).Itiseasytouseandnottime-consuming,whileitonlyservestheturningofsimpleflatpartswithuniformthickness.PandelidisandZou(1990)presentedtheoptimizationofgatelocation,byindirectqualitymeasuresrelevanttowarpageandmaterialdegradation,whichisrepresentedasweightedsumofatemperaturedifferentialterm,anover-packterm,andafrictionaloverheatingterm.Warpageisinfluencedbytheabovefactors,buttherelationshipbetweenthemisnotclear.Therefore,theoptimizationeffectisrestrictedbythedeterminationoftheweightingfactors.LeeandKim(1996b)developedanautomatedselectionmethodofgatelocation,inwhichasetofinitialgatelocationswereproposedbyadesignerandthentheoptimalgatewaslocatedbytheadjacentnodeevaluationmethod.Theconclusiontoagreatextentdependsmuchonthehumandesignersintuition,becausethefirststepofthemethodisbasedonthedesignersproposition.Sotheresultistoalargeextentlimitedtothedesignersexperience.LamandJin(2001)developedagatelocationoptimizationmethodbasedontheminimizationoftheStandardDeviationofFlowPathLength(SDL)andStandardDeviationofFillingTime(SDT)duringthemoldingfillingprocess.Subsequently,Shenetal.(2004a；2004b)optimized4thegatelocationdesignbyminimizingtheweightedsumoffillingpressure,fillingtimedifferencebetweendifferentflowpaths,temperaturedifference,andover-packpercentage.Zhaietal.(2005b)investigatedoptimalgatelocationwithevaluationcriteriaofinjectionpressureattheendoffilling.Theseresearcherspresentedtheobjectivefunctionsasperformancesofinjectionmoldingfillingoperation,whicharecorrelatedwithproductqualities.Butthecorrelationbetweentheperformancesandqualitiesisverycomplicatedandnoclearrelationshiphasbeenobservedbetweenthemyet.Itisalsodifficulttoselectappropriateweightingfactorsforeachterm.Anewobjectivefunctionispresentedheretoevaluatethewarpageofinjectionmoldedpartstooptimizegatelocation.Tomeasurepartqualitydirectly,thisinvestigationdefinesfeaturewarpagetoevaluatepartwarpage,whichisevaluatedfromthe“flowpluswarpage”simulationoutputsofMoldflowPlasticsInsight(MPI)software.Theobjectivefunctionisminimizedtoachieveminimumdeformationingatelocationoptimization.Simulatedannealingalgorithmisemployedtosearchfortheoptimalgatelocation.Anexampleisgiventoillustratetheeffectivityoftheproposedoptimizationprocedure.QUALITYMEASURES:FEATUREWARPGEDefinitionoffeaturewarpageToapplyoptimizationtheorytothegatedesign,qualitymeasuresofthepartmustbespecifiedinthefirstinstance.Theterm“quality”maybereferredtomanyproductproperties,suchasmechanical,thermal,electrical,optical,ergonomicalorgeometricalproperties.Therearetwotypesofpartqualitymeasures:directandindirect.Amodelthatpredictsthepropertiesfromnumericalsimulationresultswould